Broadway Gtk3 backend

The GDK Broadway backend provides support for displaying GTK+ applications in a web browser, using HTML5 and web sockets. To run your application in this way, select the Broadway backend by setting GDK_BACKEND=broadway. Then you can make your application appear in a web browser by pointing it at http://127.0.0.1:8080. Note that you need to enable web sockets in your web browser.

Broadway GDK backend allows multiple GTK+ applications to display their windows in the same web browser, by connecting to a Broadway display server.